Eur. Phys. J. D (2012) 66: 18
https://doi.org/10.1140/epjd/e2011-20248-3

Regular Article

Analysis of directly produce pump, signal, and idler three-color continuous-variable entanglement

School of Science, Ningbo University of Technology, Ningbo 315211, P.R. China

^a e-mail: ybyu@163.com

Received: 1 May 2011
Received in final form: 11 October 2011
Published online: 31 January 2012

Abstract

Analysis is presented in this paper to directly produce three-color continuous-variable (CV) entanglement by nondegenerate optical parametric oscillator (NOPO) with an injected signal. The quantum entanglement among the pump, signal, and idler beams are calculated by applying sufficient inseparability criteria for CV entanglement which proposed by van Loock and Furusawa [Phys. Rev. A 67, 052315 (2003)]. The results indicates that strong three-color CV entangled beams, i.e. pump, signal, and idler beams, can be generated when the NOPO operating above the threshold. The degree of entanglement dependence on damping rates is also investigated.